Kairo
Kairo is a free Android app for reading DRM-free ebooks and documents, with a standard reader and two accelerated modes: adaptive RSVP and Bionic Reading.
What Kairo is
Kairo is a free Android app for reading DRM-free ebooks and documents, with a standard reader and two accelerated modes: adaptive RSVP and Bionic Reading. Its reader includes scrollable chapters, inline images, a table of contents, bookmarks, reading progress, and a movable focus word. Adaptive RSVP uses ORP alignment and changes word timing according to punctuation, length, syllables, clauses, and readability. Bionic Reading presents timed chunks with emphasized word beginnings while keeping more sentence context visible. Reading profiles let users adjust pacing, typography, brightness, and focus, and there are six themes. Focus mode offers a full-screen reader and can optionally engage Android Do Not Disturb during a session. Kairo 1.1 supports EPUB, MOBI, PRC, AZW, FB2, FB2.ZIP, DOCX, text-based PDF, TXT, Markdown, HTML, and HTM. Files must be DRM-free; PDFs need selectable text, and scanned PDFs and OCR are not supported. Imported content and reading details remain in app-private device storage. The app has no accounts, ads, or analytics SDKs.
Good
- Includes standard, adaptive RSVP, and Bionic Reading modes
- Supports a broad range of ebook and document formats
- Offers six themes and adjustable reading profiles
- Imported files and reading details stay on-device
- No account system, ads, or analytics SDKs
Watch out
- Available only on Android
- Files must be DRM-free
- PDFs need selectable text; no OCR for scans
Who it suits
Kairo suits Android users who want to read their own DRM-free ebooks and documents, either in a standard reader or with accelerated modes. It is a fit for readers who value local storage and adjustable reading controls.
Verdict
Kairo combines conventional reading with two accelerated modes and offers detailed controls for both. Its format support is broad, but DRM-protected files and scanned PDFs are outside its stated limits.
Plans and prices
From Kairo's own pricing page, checked 9 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Kairo | Free | Free on Android 7.0 and newer · DRM-free files only |
The facts
Each one read from Kairo's own pages, with the date it was checked.
What it does
- Adaptive RSVP
- Adaptive RSVP uses ORP alignment and adjusts timing based on punctuation, word length, syllables, clauses and readability.checked 9 Oct 2026
- Audience
- Kairo is for Android users who want to read their own DRM-free ebooks and documents using standard or accelerated reading modes.checked 9 Oct 2026
- Bionic Reading
- Bionic Reading displays timed text chunks with emphasized word beginnings while keeping more sentence context visible.checked 9 Oct 2026
- File formats
- Kairo 1.1 supports EPUB, MOBI, PRC, AZW, FB2 and FB2.ZIP, DOCX, text-based PDF, TXT, Markdown, HTML and HTM files.checked 9 Oct 2026
- File limitations
- Files must be DRM-free; PDFs need selectable text, and Kairo does not support scanned PDFs or perform OCR.checked 9 Oct 2026
- Focus mode
- Focus mode provides a full-screen reader and can optionally engage Android Do Not Disturb during reading sessions.checked 9 Oct 2026
- Internet use
- Internet access supports Google Play’s flexible update flow; the site says it is not used to send reading data to a Kairo server.checked 9 Oct 2026
- Local storage
- Imported files, extracted content, reading progress, bookmarks and preferences stay in app-private storage on the device.checked 9 Oct 2026
- Open source
- Kairo is described as a native Kotlin and Jetpack Compose project whose code is available on GitHub.checked 9 Oct 2026
- Privacy
- Kairo says it has no account system, ads or analytics SDKs and does not upload users’ libraries or reading activity to a Kairo server.checked 9 Oct 2026
- Product
- Kairo is a free Android reading app for DRM-free ebooks and documents, with standard reading, adaptive RSVP and Bionic Reading modes.checked 9 Oct 2026
- Reader
- The reader supports scrollable chapters, inline images, a table of contents, bookmarks, reading progress and a movable focus word.checked 9 Oct 2026
- Reading controls
- Kairo offers reading profiles and controls for pacing, typography, brightness and focus, plus six reader themes.checked 9 Oct 2026
- Support
- The site directs users with questions about files or features to [email protected] and links to a page to support Kairo.checked 9 Oct 2026
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